The getExtensionKeys() method of Locale class in Java is used to return a set of extension keys associated with this locale which cannot be modified and the keys remains in lower-case. If there is no extension then the method returns an empty set.
Syntax:
public Set <Character> getExtensionKeys()
Parameters: This method does not take any parameters.
Return Value: This method either returns a set of extension keys associated with this locale or an empty set if it has no extensions.
Below programs illustrate the working of getExtensionKeys() method:
Program 1:
// Java code to illustrate // getExtensionKeys() method import java.util.*; public class Locale_Demo { public static void main(String[] args) { // Creating a new locale Locale first_locale = new Locale( "th" , "TH" , "TH" ); // Displaying first locale System.out.println( "Locale: " + first_locale); // Displaying the set System.out.println( "The KeySet: " + first_locale.getExtensionKeys()); } } |
Locale: th_TH_TH_#u-nu-thai The KeySet: [u]
Program 2:
// Java code to illustrate // getExtensionKeys() method import java.util.*; public class Locale_Demo { public static void main(String[] args) { // Creating a new locale Locale first_locale = new Locale( "en" , "US" ); // Displaying first locale System.out.println( "Locale: " + first_locale); // Displaying the set System.out.println( "The KeySet: " + first_locale.getExtensionKeys()); } } |
Locale: en_US The KeySet: []
Reference: https://docs.oracle.com/javase/7/docs/api/java/util/Locale.html#getExtensionKeys()